Thank you so much for having me here today. I'm a social and biological psychologist so
what that means is that I ask social kinds of questions that I use biological responses
to find the answer. So I'll typically start with a question "How does 'x' get under the
skin to affect health?" Very similarly to the director of the Greater Good Science Center,
Rudy Mendoza-Denton, who started us off this morning by telling you his own journey of
studying the darker side of the human spirit, I too, for 10-12 years, have been studying
questions like "How does discrimination get under the skin to affect health? How do social
disparities, anxiety, depression, psychopathology...," but two years ago, I saw the announcement
by the Greater Good Science Center, and one of the questions that they wanted to fund
research projects was "How might gratitude affect health and well-being?"
That wasn't typically the kind of questions I asked but I was intrigued and really challenged
by the idea at instead of looking at the worst part of humanity and how that might impair
health...Can the opposite--which is a very different kind of question... "Can something positive
be beneficial for health?" I thought this was a huge challenge but I wanted to take
it on, and so for today, I'm going to ask the question "How does gratitude get under
the skin to affect health and longevity?" Before you can get to the 'how' question,
you actually have to start with the 'does' question. Does gratitude affect health and longevity, in
a very serious, scientific, biological, deep way? Is it just that grateful people are also
less depressed and that's why they have better health? [Do] grateful people have better social
connections and it's because of those social connections that are related to health? So
we wanted to ask this in a very precise and focused way.
Now, as a social psychologist, I'll typically rely on lab experiments and the benefit of
a lab experiment is you can control every feature of the environment. I could expose
somebody to feel grateful versus a control condition, and then I can see how they change
in their endocrine responses and their autonomic nervous system responses and their behavior, and I've controlled
every feature. But, that's a very sterile environment that has lots of benefits but
lots of limitations too. So, we can also ask "Well, what about their daily lives?" People
might be very grateful at home with close others and their spouse and their children,
but then they go to work and they're sort of big jerks and they're not very grateful,
or they're students and they don't appreciate their teachers. So, looking at the social
context that people live in can tell us a lot about how they might use gratitude in
their daily experiences and how that might affect their health and biology.
We also can ask about social relationships. Are you grateful for the people around you?
Do you appreciate your social relationships? We also are interested in looking at how something
like gratitude can affect the thing that we do one-third of our lives, which is sleeping.
So, we ask all of these questions in a very broad research study. We had four specific
ideas that we wanted to test with a large sample of subjects. The first question was
"What are the individual differences in gratitude?" We all have different levels of trait gratitude.
How does that relate to health and longevity (using very deep and sophisticated biological
markers--markers that are pre-disease)? So, if you look at somebody that's already had
cardiovascular disease, their system is already disrupted and tainted. It's harder to see
what might lead them down a diseased trajectory. So, we're looking at pre-disease indicators,
the neurobiological soup that we walk around in,
our cells and our hormones and our autonomic functioning. We're looking at individual differences
in how it relates to that kind of biology. We also use experimental approaches where
we manipulate gratitude in a laboratory, but also potentiate gratitude using a hormone
called oxytocin. You might have heard about oxytocin. We all have some. Some people
have more than others. We can take oxytocin and with an intranasal spray, deliver that
neuropeptide directly to people's brains. Within about 30-40 minutes, people who get oxytocin
versus a placebo, will start having more pro-social emotions, start trusting others. So, that's
our experimental approach. We also look at a field study; how do people respond in their
daily lives, measuring their autonomic nervous system responses and their hormones as it
relates to gratitude, and then we try to put it all together, to try to make a mosaic of
what people who high versus low in gratitude look like at a biological level.
Now, I'm going to tell you a secret. It's a dirty secret about scientists, and the dirty
secret is that we all typically study one type of pathway or system, and it might not
have anything to do with the actual question, but we become an expert on a particular pathway,
and then we just keep digging into the ground on that particular pathway. I didn't want
to do that on this particular study, so I put together a team of scientists with varied
expertise so I could ask for multiple pathways, "How might gratitude influence health?" An
oxytocin pathway, a potentiated behavior pathway, vagal pathway, stress reduction [pathway]--all
these different ways that might be health-promoting. For interrelated studies--I just told you
a little about them--basically, the key factor is that we recruited a lot of people, we measured
dispositionally their gratitude, looked at their self-reported subjective experience,
their depression and anxiety, we brought a lot of them into the lab study where we gave
half of them oxytocin versus placebo, and looked how they responded to a moment of an
experimental manipulation where somebody was kind to them, helped them out of a jam, and
then looked at how that affected their physiological responses and their behavior. That is, an
acute experience of gratitude.We took a blood draw where we isolated the cells from those
individuals and then exposed those cells to various experiments that I'll tell you about.
Then, finally, we did a sleep study where we arrived at people's houses and put sensors
on them right before they went to sleep and then looked at how experiences of gratitude
affected sleep quality. So, a very broad interrelated study. To do these kinds of studies you put
sensors on people and let them live their daily lives.
So, I'm going to give you a few quick results from this study. It's still mostly ongoing
and we're putting things together. Here's what we've learned so far: When people have
higher levels of gratitude, they tend to have much better well-being, lower anxiety, higher
optimism, lower neuroticism and depression. People with higher levels of gratitude are more socially
connected. They're less likely to be rejection-sensitive or to believe that social hierarchies are a way to organize
society. They're much more interested in 'flat' social connection. They're much less likely
to be angry, and for those of you who truly practice gratitude often, your sleep quality
tends to be better the more grateful you are, and your partner reports that your sleep quality
is better. So, the idea is that it can influence those around you.
At a biological level, we find that people who are higher in gratitude have lower resting
blood pressure, and when we expose them to a stressor, they also respond with lower blood
pressure responses. We looked at their blood screen where we screened for typical cardio-metabolic
profiles, so these are the risk factors that make you susceptible to cardiovascular disease,
so good cholesterol/bad cholesterol...Higher levels of gratitude are related to higher
good cholesterol, lower bad cholesterol, and lower levels of creatinine, which is an indicator
of how functioning your kidneys are. So, it gives you an indication of how much metabolic
waste is coming through. So, the most exciting part of our data collection
(and with one minute left, I'll tell you about this very quickly), in our blood draw we isolated
the cells from individuals and we looked at this particular type of cell that's been related
to cardiovascular disease. They're called endothelial progenitor cells and these cells
help restore the vascular endophilium that are very powerful; they can regenerate. People who've
had heart disease, the lower your levels of these endothelial progenitor cells, the more
likely you are to not survive twelve months. The graph that I have up here shows survival
rates at very low levels of endophilia progenitor cells.
So, we took these progenitor cells from each of our subjects and exposed them to various
studies. So what you see here is that participants who reported something like better paternal
care... So, these are all adults, but remembering back on their childhood, and if they remember
their childhood was characterized by better paternal care--more warmth, they had better migration of
these cells. That's a good thing. Sosomething that we remembered back to thirty years ago
is related to how well our cells are functioning. At the time, we also asked about how anxious
these individuals were and higher levels of anxiety were related to worse cell functioning.
These cells both aren't moving like they're supposed to, and they're not responsive to
different reagents that we give to them. So, these studies are all ongoing and of course,
our interest is looking at these relationships to something like gratitude and how can gratitude,
both in the moment and longitudinally, be related to better health? And with that, as
I mentioned before, I obviously have this huge team of scientists who I work with and
these are just some of those individuals and I thank all of you for your time.